Combined drill and countersink



A.. SMART COMBINED vDRILL AND GOUNTERSINK- No,1298,248. y t I Patented May 6, 1884./-

(No Model.)

NA PREM Phuwulhogaphar, wand-lim D, c.

NiTED STATES.. PATENT OFFICE..

ALBEBT J. SMABT, or veBEEuvEiELD, MASSACHUSETTS, 'AssieNoE To THE WILEY & RUSSELL MANUFACTURING COMPANY, CF MASSACHUSETTS.

COMBINED 'DRILLA AND couNTERsINK.

4 SPECIFICATION forming part of Letters Patent No. 298,248, dated May 6, 1884.

A Application filed December 31, 1883. (No model.)

To @ZZ whom, it may concern:

to make and use the same.

My invention relates to that class of drills which are made use of in boring holes in metals or hard substances; and the nature thereof consists in combining with the drill a detachable and adjustable cutter for chamfering the edge of the holes cut by the drill.

It also consists in so arranging the removable cutter that one edge thereof rests in the groove or fluting of the drill, thereby strengthening the cutting-point of the cutter, and pre- Venting the drill from turning.

It also consists in combining the cutter with a ring or lcollar provided with a 'set-screw, whereby the drill and the cutter areheld firmly in position.

In the accompanying drawings, Figure lV represents the countersink with the parts thereof combined and ready for use. Fig. 2 illustrates the hollow cylinder which forms a support for the drill-spindle. Fig. 3 is the countersinlrcutter. Fig. 4 is the ring or collar. v

The drill A, of any desired length, is provided with two longitudinal* grooves, b,which are formed on its opposite sides,rand the end thereof is ground to form the cutting-point,in the usual manner.

Bis a hollow cylinder,having one of its ends beveled or chamfered to a properV angle.- This chamfered or beveled edgeis formed by turning a conical surface, c, and cutting away a portion thereof at d. The hollow cylinder B is provided with a hole or bore extending entirely through it from end to end, in order that a drill of any length can be passed through,- and that the drill may be pushed back or drawn within the cylinder. A radial slot, E, is cut in the cylinder for the reception of the cutter H, which consists of a flat bar of steel, one end of which has the shape of an acute angle, and is ground in such a manner as to form a proper' cutting-edge. When iitted in position, one edge of the cutter rests in a groove of the drill, while the other end rests in a depression, d', cut upon the interior of the ring D. The drill, the cutter, and the ring are held firmly together by means of the setscrew, I, which, upon being turned down,-

presses on the edge of the cutter, which in turn presses upon the drill. As the edge of the cutter rests within the fluting ofthe drill, it is within the hole cut by the latter. This con struction, therefore, not only holds the drill in position, but strengthensv the point ofthe cutter and prevents it from breaking or crumbfj` linfr. Y

rIjhe hollow cylinder or stock B carries the drill and also the cutter for countersinking, and i-ts point has the same angle as the cutter, which allows the latter to be set for a large or thin chip. This stock may be held in'position by the action of the set-screw I, or an additional screw may be made to work in a thread cut inthe ring D, pass through a hole cut in the stock, and press upon the drill in such a manner as to hold it and the stock firmly in position. A sufficient portion of the point of the stock, as at cl, should be cut away to allow the chips to free themselves with facility, and the longitudinal grooves b b may be made to extend the entire length of the drill, so that it :may be drawn fully out.

AIt is also to be noted that theA countersinking-cutter H may be readily detached by loosing the screws I when it is desired to sharpen, remove, or replace it.

, Having thus described my invention, I claim and desire to secure by Letters Patent of the United States-n l. The cutter, the ring or collar, having a depression for the reception of the edge of the cutter, the drill, the stock, and the set-screw, all combined, as and for the purposes de scribed.

2. i The combination of the drill, the detachf able cutter, the edge of which rests within the groove or iiuting of the drill, the ring or collar, the stock, and the set-screw, as and for the purposes described.

In testimony whereof I affix my signature in presence of witnesses.

ALBERT J. SMART.

Vitnesses:

WILLIAM H. NiMS, v J. H. SANDERSON,

CHAUNOEY BRYANT.

IOC 

